[rtp_rtcp] rtcp header structure copied from RTCPUtility and extended

webrtc/modules/rtp_rtcp/source/rtcp_packet/common_header_unittest.cc

+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/modules/rtp_rtcp/source/rtcp_packet/common_header.h"
+
+#include "testing/gtest/include/gtest/gtest.h"
+
+using webrtc::rtcp::CommonHeader;
+
+namespace webrtc {
+namespace {
+const size_t kHeaderSizeBytes = 4;
+}  // namespace
+
+TEST(RtcpCommonHeaderTest, TooSmallBuffer) {
+  uint8_t buffer[] = {0x80, 0x00, 0x00, 0x00};
+  CommonHeader header;
+  // Buffer needs to be able to hold the header.
+  EXPECT_FALSE(header.Parse(buffer, 0));
+  EXPECT_FALSE(header.Parse(buffer, 1));
+  EXPECT_FALSE(header.Parse(buffer, 2));
+  EXPECT_FALSE(header.Parse(buffer, 3));
+  EXPECT_TRUE(header.Parse(buffer, 4));
+}
+
+TEST(RtcpCommonHeaderTest, Version) {
+  uint8_t buffer[] = {0x00, 0x00, 0x00, 0x00};
+  CommonHeader header;
+  // Version 2 is the only allowed.
+  buffer[0] = 0 << 6;
+  EXPECT_FALSE(header.Parse(buffer, sizeof(buffer)));
+  buffer[0] = 1 << 6;
+  EXPECT_FALSE(header.Parse(buffer, sizeof(buffer)));
+  buffer[0] = 2 << 6;
+  EXPECT_TRUE(header.Parse(buffer, sizeof(buffer)));
+  buffer[0] = 3 << 6;
+  EXPECT_FALSE(header.Parse(buffer, sizeof(buffer)));
+}
+
+TEST(RtcpCommonHeaderTest, PacketSize) {
+  uint8_t buffer[] = {0x80, 0x00, 0x00, 0x02,
+                      0x00, 0x00, 0x00, 0x00,
+                      0x00, 0x00, 0x00, 0x00};
+  CommonHeader header;
+  EXPECT_FALSE(header.Parse(buffer, sizeof(buffer) - 1));
+  EXPECT_TRUE(header.Parse(buffer, sizeof(buffer)));
+  EXPECT_EQ(8u, header.payload_size_bytes());
+  EXPECT_EQ(buffer + sizeof(buffer), header.NextPacket());
+}
+
+TEST(RtcpCommonHeaderTest, PaddingAndPayloadSize) {
+  // Set v = 2, p = 1, but leave fmt, pt as 0.
+  uint8_t buffer[] = {0xa0, 0x00, 0x00, 0x00,
+                      0x00, 0x00, 0x00, 0x00,
+                      0x00, 0x00, 0x00, 0x00};
+  CommonHeader header;
+  // Padding bit set, but no byte for padding (can't specify padding length).
+  EXPECT_FALSE(header.Parse(buffer, 4));
+
+  buffer[3] = 2;  //  Set payload size to 2x32bit.
+  const size_t kPayloadSizeBytes = buffer[3] * 4;
+  const size_t kPaddingAddress = kHeaderSizeBytes + kPayloadSizeBytes - 1;
+
+  // Padding one byte larger than possible.
+  buffer[kPaddingAddress] = kPayloadSizeBytes + 1;
+  EXPECT_FALSE(header.Parse(buffer, sizeof(buffer)));
+
+  // Invalid zero padding size.
+  buffer[kPaddingAddress] = 0;
+  EXPECT_FALSE(header.Parse(buffer, sizeof(buffer)));
+
+  // Pure padding packet.
+  buffer[kPaddingAddress] = kPayloadSizeBytes;
+  EXPECT_TRUE(header.Parse(buffer, sizeof(buffer)));
+  EXPECT_EQ(0u, header.payload_size_bytes());
+  EXPECT_EQ(buffer + sizeof(buffer), header.NextPacket());
+  EXPECT_EQ(header.payload(), buffer + kHeaderSizeBytes);
+
+  // Single byte of actual data.
+  buffer[kPaddingAddress] = kPayloadSizeBytes - 1;
+  EXPECT_TRUE(header.Parse(buffer, sizeof(buffer)));
+  EXPECT_EQ(1u, header.payload_size_bytes());
+  EXPECT_EQ(buffer + sizeof(buffer), header.NextPacket());
+}
+
+TEST(RtcpCommonHeaderTest, FormatAndPayloadType) {
+  uint8_t buffer[] = {0x9e, 0xab, 0x00, 0x00};
+  CommonHeader header;
+  EXPECT_TRUE(header.Parse(buffer, sizeof(buffer)));
+
+  EXPECT_EQ(header.count(), 0x1e);
+  EXPECT_EQ(header.fmt(), 0x1e);
+  EXPECT_EQ(header.type(), 0xab);
+  EXPECT_EQ(header.payload_size_bytes(), 0u);
+  EXPECT_EQ(header.payload(), buffer + kHeaderSizeBytes);
+}
+}  // namespace webrtc